Abstract: Zooplankton are a central issue in the ecology which makes a great contribution to maintaining the balance of an ecosystem. It is critical in promoting the material cycle and energy flow within the ecosystems. A generalized additive model (GAM) was applied to analyze the relationships between the density (individuals per m³) of zooplankton and other variables in West Daya Bay. All data used in this analysis (the survey month, survey station (longitude and latitude), the depth of the water column, the superficial concentration of chlorophyll a, the benthonic concentration of chlorophyll a, the number of zooplankton species and the number of zooplankton species) were collected through monthly scientific surveys during January to December 2016. GLM model (generalized linear model) was used to choose the significant variables’ impact on the density of zooplankton, and the GAM was employed to analyze the relationship between the density of zooplankton and the significant variables. The results showed that the density of zooplankton increased with an increase of the benthonic concentration of chlorophyll a, but decreased with a decrease in the depth of the water column. Both high numbers of zooplankton species and the overall total number of zooplankton individuals led to a higher density of zooplankton.
Abstract: In 2010-2011, the research on zooplankton was
conducted in the southern part of the Baltic Sea to determine seasonal
variability in changes occurring throughout the zooplankton in 2010
and 2011, both in the region of Gdańsk Deep, and in the western part
of Gdańsk Bay. The research in the sea showed that the taxonomic
composition of holoplankton in the southern part of the Baltic Sea
was similar to that recorded in this region for many years. The
maximum values of abundance and biomass of zooplankton both in
the Deep and the Bay of Gdańsk were observed in the summer
season. Copepoda dominated in the composition of zooplankton for
almost the entire study period, while rotifers occurred in larger
numbers only in the summer 2010 in the Gdańsk Deep as well as in
May and July 2010 in the western part of Gdańsk Bay, and
meroplankton – in April 2011.